.\" Copyright (c) 2002 Tim J. Robbins
.\" All rights reserved.
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.\" $FreeBSD: src/lib/libc/string/wcswidth.3,v 1.2 2002/12/09 14:04:05 ru Exp $
.\"
.Dd August 20, 2002
.Dt WCSWIDTH 3
.Os
.Sh NAME
.Nm wcswidth ,
.Nm wcswidth_l
.Nd "number of column positions in wide-character string"
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In wchar.h
.Ft int
.Fo wcswidth
.Fa "const wchar_t *pwcs"
.Fa "size_t n"
.Fc
.In wchar.h
.In xlocale.h
.Ft int
.Fo wcswidth_l
.Fa "const wchar_t *pwcs"
.Fa "size_t n"
.Fa "locale_t loc"
.Fc
.Sh DESCRIPTION
The
.Fn wcswidth
function determines the number of column positions required for the first
.Fa n
characters of
.Fa pwcs ,
or until a null wide character (L'\e0') is encountered.
.Pp
Although the
.Fn wcswidth
function uses the current locale, the
.Fn wcswidth_l
function may be passed a locale directly. See
.Xr xlocale 3
for more information.
.Sh RETURN VALUES
The
.Fn wcswidth
function returns 0 if
.Fa pwcs
is an empty string (L""),
\-1 if a non-printing wide character is encountered;
otherwise, it returns the number of column positions occupied.
.Sh SEE ALSO
.Xr iswprint 3 ,
.Xr wcwidth 3 ,
.Xr xlocale 3
.Sh STANDARDS
The
.Fn wcswidth
function conforms to
.St -p1003.1-2001 .
